Phase I clinical trial of multiple-peptide vaccination for patients with advanced biliary tract cancer.

BACKGROUND: The prognosis of patients with advanced biliary tract cancer (BTC) is extremely poor and only a few standard treatments are available for this condition. We performed a phase I trial to investigate the safety, immune response and anti-tumor effect of vaccination with three peptides derived from cancer-testis antigens. METHODS: This study was conducted as a phase I trial. Nine patients with advanced BTC who had unresectable tumors and were refractory to standard chemotherapy were enrolled. Three HLA-A*2402 restricted epitope peptides-cell division cycle associated 1 (CDCA1), cadherin 3 (CDH3) and kinesin family member 20A (KIF20A)-were administered subcutaneously, and the adverse events and immune response were assessed. The clinical effects observed were the tumor response, progression-free survival (PFS) and overall survival (OS). RESULTS: The three-peptide vaccination was well-tolerated up to a dose of 3 mg per peptide (9 mg total). No grade 3 or 4 adverse events were observed after vaccination. Peptide-specific T cell immune responses were observed in all patients and stable disease was observed in 5 of 9 patients. The median PFS and OS were 3.4 and 9.7 months. The Grade 2 injection site reaction and continuous vaccination after PD judgment appeared to be prognostic of OS. CONCLUSIONS: Multiple-peptide vaccination was well tolerated and induced peptide-specific T-cell responses. TRIAL REGISTRATION: This study was registered with the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR000003229).

Enhancement of 5-fluorouracil-induced cytotoxicity by leucovorin in 5-fluorouracil-resistant gastric cancer cells with upregulated expression of thymidylate synthase.

BACKGROUND: Elucidation of the mechanisms by which gastric cancer cells acquire resistance to 5-fluorouracil (5FU) may provide important clues to the development of effective chemotherapy for 5FU-resistant gastric cancer METHODS: Four 5FU-resistant cell lines (MKN45/5FU, MKN74/5FU, NCI-N87/5FU, and KATOIII/5FU) were established by continuous exposure of the cells to progressively increasing concentrations of 5FU for about 1 year. Then, mRNA expression levels of four genes associated with 5FU metabolism, i.e., thymidylate synthase (TS), dihydropyrimidine dehydrogenase, thymidine phosphorylase, and orotate phosphoribosyltransferase, were quantitatively evaluated by real-time reverse transcriptase-polymerase chain reaction. In addition, TS protein expression was measured by Western blot analysis. RESULTS: As compared with the parent cell lines, the 5FU-resistant cell lines showed 3.8- to 11.6-fold higher resistance to 5FU, as well as 1.9- to 3.5-fold higher TS mRNA expression and 1.6- to 7.1-fold higher TS protein expression. In contrast, the expressions of other genes did not differ significantly among the cell lines. The cytotoxicity of 5FU was enhanced 2.3- to 2.8 fold by leucovorin (LV) against three of the four 5FU-resistant cell lines. CONCLUSIONS: Collectively, LV enhanced the cytotoxicity of 5FU not only against the parent gastric cancer cell lines, but also against the 5FU-resistant cell lines, even those with elevated TS expression levels. These results suggest that clinical studies of a combination of 5FU and LV are warranted in patients who have recurrent gastric cancer after 5FU-based therapy.

[The case of tumor escape mechanism by changing their tumor-associated antigens].

A 53-year-old woman presented with a diagnosis of advanced gallbladder cancer at our hospital. She was evaluated with CT scan and given a diagnosis of Stage IVb due to the multiple lymph nodes metastases and significant invasion to the artery. However, we underwent simple cholecystectomy followed by immunotherapy that was the hope of herself and her family. The serum level of DUPAN-2 was gradually elevated to 6,800 U/mL, and the metastases to the liver were detected. After we started the dendritic cell vaccine pulsed with autologous tumor-lysate with S-1, DUPAN-2 decreased to 980 U/ mL. The CT scan showed complete response (CR) in the liver metastases and partial response (PR) in the lymph node metastases. However, the serum level of CEA elevated since the MUC-1 peptide was used instead of autologous tumor- lysate, even DUPAN-2 did not. The liver metastases were in control, but the lymph nodes metastases had progressed. She died of the progressed lesion later in approximately one year from the operation. This case demonstrated a possibility of the tumor escape mechanism by changing their tumor-associated antigens.

Phase II study of bevacizumab and irinotecan as second-line therapy for patients with metastatic colorectal cancer previously treated with fluoropyrimidines, oxaliplatin, and bevacizumab.

PURPOSE: Fluorouracil and folinic acid with irinotecan (FOLFIRI) plus bevacizumab (BV) is widely used as second-line chemotherapy for patients with metastatic colorectal cancer (mCRC) previously treated with fluoropyrimidines, oxaliplatin, and BV. FOLFIRI requires a CV catheter and an infusion pump, which are inconvenient for patients. Sufficient data are not available for characterizing the effectiveness of fluoropyrimidines beyond first disease progression. In this study, we evaluated the efficacy and safety of irinotecan (CPT-11) plus BV as second-line therapy. METHODS: Patients with mCRC previously treated with at least four courses of a fluoropyrimidine, oxaliplatin, and BV were designated to receive 150 mg/m2 of CPT-11 and 10 mg/kg of BV every 2 weeks as second-line therapy. The primary endpoint was progression-free survival (PFS), and secondary endpoints included response rate (RR), overall survival (OS), and adverse events. RESULTS: Thirty patients from six institutes were enrolled from March 2011 to January 2014. The median PFS was 5.7 months (95% CI 4.2-7.3 months), and the RR was 6.7% (range 0.8-22.1%). Grades 3-4 adverse events included leucopenia (36.7%), neutropenia (50%), thrombocytopenia (26.7%), anemia (30%), diarrhea (3.3%), anorexia (6.7%), and hypertension (3.3%). Relative dose intensities were 94.5 and 96.3% for CPT-11 and BV, respectively. The median OS was 11.8 months (6.3 months-not reached). CONCLUSIONS: Administration of CPT-11 plus BV to patients with mCRC achieved comparable efficacies with relatively lower toxicities compared with the results of previous studies using FOLFIRI plus BV as second-line therapy. The dose intensity of CPT-11 was judged as satisfactory. CLINICAL TRIAL INFORMATION: UMIN000005228.

Anti-CD137 monoclonal antibody administration augments the antitumor efficacy of dendritic cell-based vaccines.

In weakly and poorly immunogenic tumor models, we examined the effects of stimulating CD137 (4-1BB) in vivo by administering anti-CD137 monoclonal antibody after tumor lysate-pulsed dendritic cell (TP-DC) vaccination. TP-DC subcutaneous vaccination induced a transient up-regulation of CD137 on T cells and natural killer (NK) cells within vaccine-primed lymph nodes (VPLNs). In established pulmonary and subcutaneous tumor models, anti-CD137 synergistically enhanced tumor regression after TP-DC vaccination. In the subcutaneous tumor model, the combined therapy resulted in improved survival. Combined therapy also resulted in improved local control of subcutaneous tumor after surgical resection. Anti-CD137 polarized the cytokine release of VPLNs and spleen cells in response to tumor antigen toward a type 1 (interferon-gamma) versus a type 2 (interleukin-4) profile. Cell depletion and the use of knockout animals identified that CD8(+), CD4(+), and NK cells were involved in the tumor rejection response and that CD8(+) cells had the major effector role. Anti-CD137 administration resulted in increased proliferation of adoptively transferred OT-1 CD8(+) T cells in the VPLNs of mice inoculated with B16-OVA TP-DCs. Polarization toward type 1 (interferon-gamma) versus type 2 (interleukin-4) was also observed with the OT-1 cells from VPLNs and spleen cells after anti-CD137 injections. This polarization effect was abrogated by the in vivo depletion of NK cells. These findings indicate that the adjuvant effect of anti-CD137 given in conjunction with TP-DC vaccination is associated with the polarization of T effector cells toward a type 1 response to tumor antigen and is mediated via NK cells.

Immunological responses to a multi-peptide vaccine targeting cancer-testis antigens and VEGFRs in advanced pancreatic cancer patients.

The prognosis of patients with advanced pancreatic cancer is extremely poor and there are only a few standard treatments. Here, we report the results of a Phase I clinical trial to investigate the safety, immunostimulatory effects, and antineoplastic activity of a multi-target vaccine composed of four distinct peptides derived from cancer-testis (CT) antigens and vascular endothelial growth factor receptors (VEGFRs). Nine patients with unresectable, advanced pancreatic cancer who were refractory to standard chemotherapy were enrolled. Each patient was vaccinated with HLA-A*2402-restricted peptides derived from the CT antigens kinesin family member 20A (KIF20A) and cell division cycle-associated 1 (CDCA1) as well as from VEGFR1 and VEGFR2 subcutaneously once a week, and disease progression was evaluated up to 6 mo later. Adverse events were assessed using the Common Terminology Criteria for Adverse Events v. 3.0. Immunological responses were monitored by ELISPOT assays and flow cytometry based on peptide-specific dextramers. The clinical outcomes that were measured were tumor response, progression-free survival (PFS) and overall survival (OS). In general, the multi-peptide vaccine was well-tolerated, and no grade 3 or 4 adverse events were observed upon vaccination. Peptide-specific T-cell responses were detected in all 9 patients, and clinical benefits were observed in four of them. Median PFS and OS were 90 and 207 d, respectively. The elicitation of multiple and robust peptide-specific T-cell responses as well as the status of host lymphocytes may be useful prognostic factors among patients with advanced pancreatic cancer treated with peptide-based anticancer vaccines.

Long-term Vaccination with Multiple Peptides Derived from Cancer-Testis Antigens Can Maintain a Specific T-cell Response and Achieve Disease Stability in Advanced Biliary Tract Cancer.

PURPOSE: The prognosis of patients with advanced biliary tract cancer (BTC) is extremely poor and there are only a few standard treatments. We conducted a phase I trial to investigate the safety, immune response, and antitumor effect of vaccination with four peptides derived from cancer-testis antigens, with a focus on their fluctuations during long-term vaccination until the disease had progressed. EXPERIMENTAL DESIGN: Nine patients with advanced BTC who had unresectable tumors and were refractory to standard chemotherapy were enrolled. HLA-A*2402-restricted epitope peptides, lymphocyte antigen 6 complex locus K, TTK protein kinase, insulin-like growth factor-II mRNA-binding protein 3, and DEP domain containing 1 were vaccinated subcutaneously once a week at doses of 0.5, 1, or 2 mg and continued until disease progression. The adverse events were assessed by Common Terminology Criteria for Adverse Events and the immune response was monitored by an enzyme-linked immunospot assay or by flow cytometry. The clinical effects observed were tumor response, progression-free survival (PFS), and overall survival (OS). RESULTS: Four-peptide vaccination was well tolerated. No grade 3 or 4 adverse events were observed. Peptide-specific T-cell immune responses were observed in seven of nine patients and clinical responses were observed in six of nine patients. The median PFS and OS were 156 and 380 days. The injection site reaction and CTL induction seemed to be prognostic factors of both PFS and OS. CONCLUSIONS: Four-peptide vaccination was well tolerated and seemed to provide some clinical benefit to some patients. These immunologic and clinical responses were maintained over the long term through continuous vaccinations.

Phase I trial of Wilms' Tumor 1 (WT1) peptide vaccine with GM-CSF or CpG in patients with solid malignancy.

BACKGROUND: The aim of this study was to investigate the safety and efficacy of combinatorial use of granulocyte-macrophage colony-stimulating factor (GM-CSF) and CpG oligodeoxynucleotides (CpG-ODN) as immunoenhancement adjuvants in Wilms' Tumor 1 (WT1) vaccine therapy for patients with solid malignancy. PATIENTS AND METHODS: The patients were placed into treatment groups as follows: WT1 peptide alone, WT1 peptide with GM-CSF (100 µg) and WT1 peptide with CpG-ODN (100 µg). HLA-A *2402 or *0201/*0206-restricted, WT1 peptide emulsified with Montanide ISA51 was injected intradermally every week for eight weeks. Toxicities were evaluated according to the National Cancer Institute Common Terminology Criteria for Adverse Events ver. 3.0. Tumor size, which was measured by computed tomography, was determined every four weeks. The responses were analyzed according to Response Evaluation Criteria in Solid Tumors. RESULTS: The protocol was well tolerated; only local erythema occurred at the WT1 vaccine injection site. The disease control rate of the groups treated with WT1 peptide alone (n=10), with combinatorial use of GM-CSF (n=8) and with combinatorial use of CpG-ODN (n=10), in the initial two months was 20%, 25% and 60%, respectively. CONCLUSION: Addition of GM-CSF or CpG-ODN to the WT1 peptide vaccine for patients with solid malignancy was safe and improved the effectiveness of clinical response.

Determination of chronic inflammatory states in cancer patients using assay of reactive oxygen species production by neutrophils.

BACKGROUND: Although the systemic inflammatory condition can be confirmed in cancer patients, the pathophysiological importance of reactive oxygen species (ROS) produced by neutrophils has not yet been defined. PATIENTS AND METHODS: Twenty-one patients with inoperable, chemoresistant and radioresistant cancer were enrolled in this study. At least 4 weeks prior to sampling, the patients were free from antitumor treatments. Control samples were also obtained from a healthy donor (39-year-old male). Peripheral blood samples were set 150 µl each on the 2 ml tube with 50 µl Mebiol Gel, and the production of ROS from neutrophils was detected by luminol-dependent chemiluminescence (LmCL) in a kinetic mode at 30-minute intervals for 2.5 hours with a luminometer at 37°C. RESULTS: Each point, peak value and sum of values of LmCL in the patient group was statistically higher than those in the healthy donor. There were no differences in LmCL according to performance status (PS), type of cancer, age, or gender in cancer patients. CONCLUSION: Our findings suggested that ROS produced by neutrophils universally reflects the systemic inflammatory condition in cancer patients.

Effect of green tea extract on reactive oxygen species produced by neutrophils from cancer patients.

BACKGROUND/AIM: Oxidative stress in cancer patients has been demonstrated to be partly mediated by neutrophils. Although it is reported that natural antioxidants, such as green tea extract, reduce oxidative stress, there is limited evidence of their effects in cancer patients. This study aimed to determine the effect of green tea extract on reactive oxygen species produced by neutrophils from cancer patients. MATERIALS AND METHODS: Peripheral blood samples were obtained from eighteen patients with advanced cancer. Green tea extract was added to the blood samples with luminol on Mebiol gel, and luminol-dependent chemiluminescence was measured to monitor the production of reactive oxygen species from migrated neutrophils into the gel, at 37°C. RESULTS: Luminol-dependent chemiluminescence was significantly down-regulated in the presence of green tea extract in a concentration-dependent manner. CONCLUSION: These results indicate the antioxidant effect of green tea extract on reactive oxygen species produced by neutrophils, which may be effective in reducing oxidative stress in cancer patients.

Impact of dihydropyrimidine dehydrogenase and γ-glutamyl hydrolase on the outcomes of patients treated with gemcitabine or S-1 as adjuvant chemotherapy for advanced pancreatic cancer.

Gene expression analyses may play useful roles in determining the prognosis of cancer patients and in selecting antitumor drugs. This retrospective study examined potential prognostic factors in patients with pancreatic cancer who received adjuvant chemotherapy after surgery. The study group consisted of 79 patients who had received gemcitabine or S-1 as adjuvant chemotherapy for advanced pancreatic cancer. Using laser-captured microdissection and real-time RT-PCR assay, we quantitatively evaluated the mRNA levels of 10 genes associated with patient prognosis and sensitivity to chemotherapy using paraffin-embedded specimens of the primary tumors resected before the start of adjuvant chemotherapy. In univariate analyses, a low gene expression level of γ-glutamyl hydrolase (GGH) and a high gene expression level of folylpolyglutamate synthase correlated with a favorable outcome. In a multivariate analysis, a low gene expression level of dihydropyrimidine dehydrogenase (DPD) and GGH significantly correlated with outcome (hazard ratio of the high DPD group to the low DPD group: 5.55; 95% confidence interval (CI) 1.27-24.05; P=0.022; the high GGH group to the low GGH group: 3.77; 95% CI 1.04-13.79, P=0.043). For adjuvant chemotherapy of patients with pancreatic cancer, the mRNA level of DPD and GGH may affect the prognosis of these patients.

Mechanisms involved in radiation enhancement of intratumoral dendritic cell therapy.

We have previously reported that local tumor irradiation, without inducing cell death, can augment the therapeutic efficacy of intratumoral (IT) dendritic cell (DC) vaccination. This study examined potential mechanisms underlying radiation enhancement of IT DC therapy in this setting. Even though ionizing radiation did not mediate tumor cell killing, bone marrow-derived DCs acquired in vitro tumor antigens from irradiated D5 murine melanoma cells more efficiently than from untreated cells. This radiation-enhanced loading of DCs did not induce DC maturation, but was associated with improved cross-priming of T cells both in vitro and in vivo. Furthermore, in vivo pulsing of DCs with irradiated versus untreated tumor cells resulted in superior presentation of tumor antigens to T cells. In addition, tumor irradiation facilitated homing of IT administered DCs to the draining lymph node, possibly by down-regulating CCL21 expression within the tumor mass. Studies of the tumor microenvironment in irradiated versus untreated tumors did not reveal significant inflammatory changes. Moreover, radiation did not promote accumulation of CD4 or CD8 effector T cells within solid tumors. Our results indicate that, without inducing cytotoxicity, tumor irradiation can enhance the ability of DCs to capture tumor antigens, migrate to the draining lymph node, and present processed antigens to T cells. These findings may prove useful in designing future strategies for human cancer immunotherapy.